Reducing the University of Virginia’s environmental impact is something in which everyone at the institution is involved.

That was the message from Pat Hogan, executive vice president and chief operating officer, David Neuman, the University’s architect and chair of the University’s Sustainability Committee, and two student researchers who explained the concept of a nitrogen footprint to a crowd of approximately 240 students, faculty, staff and community members attending Wednesday’s U.Va. Earth Week Expo at Newcomb Hall.

“When we formed the Sustainability Committee in 2008, there were already so many sustainability efforts under way,” Neuman said. “We didn’t want the committee to become institutionalized with a vice president for sustainability. It is all of our jobs.”

The speakers were the centerpiece of the exposition, which also included exhibits, demonstrations, activities and a vegetarian lunch that reinforced the University’s sustainability mission.

Hogan, who opened the program, outlined several steps the University has taken to improve its environmental interaction, such as encouraging composting, recycling and car-pooling and creating “Delta Force,” an inter-departmental task force that re-commissions buildings to reduce their energy and water usage.

“So far, the Delta Force team has ‘retro-commissioned’ 28 buildings, for a cost savings of nearly $11 million,” he said. “At the same time, their work has saved 21,000 metric tons of carbon dioxide. It might be hard to picture what 21,000 metric ton equivalents of carbon dioxide is. It would be the same as driving a car to the moon and back 150 times.”

Hogan introduced Allison Leach, a graduate student in the Department of Environmental Sciences, and Ariel Majidi, a fourth-year biochemistry major, both in the College of Arts & Sciences, and cited their work measuring the University’s nitrogen footprint. Leach is working with professor James Galloway, Sidman P. Poole Professor of Environmental Sciences, to develop a preliminary nitrogen footprint model for the University.

The vast majority of nitrogen is harmless inert gas, as well as an essential element in fertilizer and many other uses. The remainder, called “reactive nitrogen,” is found in a variety of forms, including as nitrate, ammonia and nitric oxide, and it interacts with elements of the environment to create smog – increasing levels of ozone at the Earth’s surface, acidifying the water and weakening the upper-atmosphere’s ozone layer.

“Because of the work of these two women and others, U.Va. is the first school in the nation to measure our nitrogen footprint,” Hogan said. “Institutions and universities around the world are becoming interested in how they can apply this model to their organizations.”

The Sustainability Committee has recommended reducing the University’s nitrogen footprint by 25 percent from 2009 levels by 2025. The Faculty Senate has approved the recommendation and the Student Council, the General Faculty Council and the employee councils will consider it. The University has already pledged to reduce greenhouse gas emissions to 250,000 metric tons by 2025, also 25 percent below 2009 levels.

Leach discussed the need to balance the use of inert hydrogen, which is necessary for life and food production, with the production of reactive nitrogen, which has negative affects on human health.

“The challenge is to optimize the use of nitrogen while minimizing the negative impacts,” Leach said.

She said the nitrogen dilemma could be addressed with technology, changes in policy and individual and institutional actions. As an example, new technology could better control the amount of fertilizer used on crops, she said.

She called on individuals to reduce their electricity and waste, and increase their recycling and utilization of public transportation. She suggested people eat only the recommended amount of protein and consume less animal protein, eat less nitrogen-intensive meats and reduce food waste.

As an example, Leach said a half-cup of beans and a 3-ounce steak each provide about 15 grams of protein, but more nitrogen is released producing the steak than the beans.

She cited that day’s vegetarian lunch, which consisted mostly of locally sourced foods. That lunch, Leach said, had a nitrogen footprint of about 20 grams per person, whereas a lunch with chicken would have generated about 30 grams of nitrogen and a lunch with beef would have generated 50 grams of nitrogen per person.

“I’m not saying you need to go vegetarian,” Leach said, “just that using poultry is more nitrogen-friendly than beef.”

In determining the University’s nitrogen footprint, Leach calculated about 45 percent comes from utilities and 39 percent from food production. Other nitrogen generators include transportation, fertilizer use and waste.

Majidi, the undergraduate student researching the University’s nitrogen footprint, said that steps that the University can take to reduce its nitrogen footprint include improving sewage treatment, reducing energy use, expanding composting and food recycling and offering more sustainable food options. She said the University is fortunate that the Rivanna Water and Sewer Authority has upgraded its sewage treatment system, which reduces nitrogen.

She said that since the University began working to reduce its greenhouse gas emissions, it has reduced its energy consumption, encouraged alternative modes of transportation and increased composting while reducing food waste. She suggested students get involved with environmental groups on Grounds and encourage U.Va. Dining Services to continue its sustainability efforts.

She said many of the things being done to reduce the University’s carbon footprint also influence the nitrogen footprint.

Neuman said that University researchers are conducting a great deal of cutting-edge research, such as Galloway’s work. He said part of the key to the work at U.Va is high level of collaboration among departments.

“U.Va. has to be out front, and because it is an educational institution it has to lead by example,” he said.

But he also noted that being a leading institution in sustainability does not mean that U.Va. surrenders its past. The University has 22 buildings with a Leadership in Energy and Environmental Design certification, most at the silver and gold levels, but Neuman said the University has also received LEED certification for one of the original Thomas Jefferson-designed buildings – Pavilion IX.

“I think Harvard University has one now as well, but for awhile, we were the only university in the country with a 18th-century building with LEED certification,” Neuman said.